Richardson Mark B, Gabriel Kristin N, Garcia Joseph A, Ashby Shareen N, Dyer Rebekah P, Kim Joshua K, Lau Calvin J, Hong John, Le Tourneau Ryan J, Sen Sanjana, Narel David L, Katz Benjamin B, Ziller Joseph W, Majumdar Sudipta, Collins Philip G, Weiss Gregory A
Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States.
Department of Molecular Biology & Biochemistry, University of California, Irvine, Irvine, California 92697, United States.
Bioconjug Chem. 2020 May 20;31(5):1449-1462. doi: 10.1021/acs.bioconjchem.0c00143. Epub 2020 Apr 30.
Advances in bioconjugation, the ability to link biomolecules to each other, small molecules, surfaces, and more, can spur the development of advanced materials and therapeutics. We have discovered that pyrocinchonimide, the dimethylated analogue of maleimide, undergoes a surprising transformation with biomolecules. The reaction targets amines and involves an imide transfer, which has not been previously reported for bioconjugation purposes. Despite their similarity to maleimides, pyrocinchonimides do not react with free thiols. Though both lysine residues and the -termini of proteins can receive the transferred imide, the reaction also exhibits a marked preference for certain amines that cannot solely be ascribed to solvent accessibility. This property is peculiar among amine-targeting reactions and can reduce combinatorial diversity when many available reactive amines are available, such as in the formation of antibody-drug conjugates. Unlike amides, the modification undergoes very slow reversion under high pH conditions. The reaction offers a thermodynamically controlled route to single or multiple modifications of proteins for a wide range of applications.
生物共轭技术的进展，即将生物分子彼此连接、与小分子连接、与表面连接等的能力，能够推动先进材料和治疗方法的发展。我们发现，马来酰亚胺的二甲基化类似物焦脱镁叶绿酸亚胺与生物分子会发生惊人的转变。该反应以胺为目标，涉及酰亚胺转移，这在之前的生物共轭应用中尚未有报道。尽管焦脱镁叶绿酸亚胺与马来酰亚胺相似，但它们不与游离硫醇反应。虽然赖氨酸残基和蛋白质的N端都能接受转移的酰亚胺，但该反应对某些胺也表现出明显的偏好，而这种偏好不能仅仅归因于溶剂可及性。这种特性在针对胺的反应中很独特，当有许多可用的反应性胺时，如在抗体 - 药物偶联物的形成中，它会降低组合多样性。与酰胺不同，该修饰在高pH条件下的逆转非常缓慢。该反应为蛋白质的单修饰或多修饰提供了一条热力学可控的途径，可用于广泛应用。
